The Health Effects of Climate Change: An Overview of Systematic Reviews

Rocque, R.; Beaudoin, C.; Ndjaboue, R.; Cameron, L.; Poirier-Bergeron, L.; Poulin-Rheault, R.-A.; Fallon, C.; Tricco, A.; Witteman, H.

Background: Although many studies have explored the health impacts of climate change, a broader overview of research is needed to guide future research and action to mitigate and adapt to the health impacts of climate change. Methods: We conducted an overview of systematic reviews of health impacts of climate change. We systematically searched the literature using a predefined search strategy, inclusion, and exclusion criteria. We included systematic reviews that explored at least one health impact of climate change. We organized systematic reviews according to their key characteristics, including geographical regions, year of publication and authors' affiliations. We mapped the climate effects and health outcomes being studied and synthesized major findings. Findings: We included ninety-four systematic reviews. Most were published after 2015 and approximately one fifth contained meta-analyses. Reviews synthesized evidence about five categories of climate impacts; the two most common were meteorological and extreme weather events. Reviews covered ten health outcome categories; the three most common were 1) infectious diseases, 2) mortality, and 3) respiratory, cardiovascular, cardiopulmonary or neurological outcomes. Most reviews suggested a deleterious impact of climate change on multiple adverse health outcomes, although the majority also called for more research. Interpretation: Overall, most systematic reviews suggest that climate change is associated with worse human health. Future research could explore the potential explanations between these associations to propose adaptation and mitigation strategies and could include psychological and broader social health impacts of climate change. Funding: Canadian Institutes of Health Research FDN-148426